Volkswagen: test FW version format (#32162)

* add test

* more explicit

selfdrive/car/volkswagen/tests/test_volkswagen.py

@@ -0,0 +1,19 @@
+#!/usr/bin/env python3
+import unittest
+
+from openpilot.selfdrive.car.volkswagen.values import SPARE_PART_FW_PATTERN
+from openpilot.selfdrive.car.volkswagen.fingerprints import FW_VERSIONS
+
+
+class TestVolkswagenPlatformConfigs(unittest.TestCase):
+  def test_spare_part_fw_pattern(self):
+    # Relied on for determining if a FW is likely VW
+    for platform, ecus in FW_VERSIONS.items():
+      with self.subTest(platform=platform):
+        for fws in ecus.values():
+          for fw in fws:
+            self.assertNotEqual(SPARE_PART_FW_PATTERN.match(fw), None, f"Bad FW: {fw}")
+
+
+if __name__ == "__main__":
+  unittest.main()

selfdrive/car/volkswagen/values.py

@@ -1,6 +1,7 @@
 from collections import namedtuple
 from dataclasses import dataclass, field
 from enum import Enum, IntFlag
+import re
 
 from cereal import car
 from panda.python import uds
@@ -362,6 +363,9 @@ class CAR(Platforms):
 
 VOLKSWAGEN_RX_OFFSET = 0x6a
 
+# TODO: determine the unknown groups
+SPARE_PART_FW_PATTERN = re.compile(b'\xf1\x87(?P<gateway>[0-9][0-9A-Z]{2})(?P<unknown>[0-9][0-9A-Z][0-9])(?P<unknown2>[0-9A-Z]{2}[0-9])([A-Z0-9]| )')
+
 FW_QUERY_CONFIG = FwQueryConfig(
   # TODO: add back whitelists after we gather enough data
   requests=[request for bus, obd_multiplexing in [(1, True), (1, False), (0, False)] for request in [